Dome-shaped roof



Jan. 15, 1952 R, STEMMQNS HAL 2 2,582,723

DOME SHAPED ROOF Filed March 10, 1948 3 Sheets-Sheet l .INVENTORS Iva/fer L fde/ BY Poerf fifemmoms ATTORNEY Jan. 15, 1952 R. STEMMONS ETAL DOME SHAPED ROOF 5 Sheets-Sheet 2 Filed March 10, 1948 IN V EN TORS Wo/fer L Eoe/ Robe/'2 Jfemmons M M ATTORNEY R. STEMMONS ET AL Jan. 15, 1952 DOME SHAPED ROOF 3 Sheets-Sheet 3 Filed March 10, 1948 INVENTORJ IMO/fer L Eoe/ Robe/v S/emmpms ATTORNEY Patented Jan. 15, 1952 UNITED STATES PATENT OFFICE. assazzs v DOME-SHAPED ROOF I Robert Stemmonslmddletown, Ohio, and Walter L'. Edel, Louisville; Ky, assignorsv to: Clayton. .&

Lambert .Manufacturing Company, Louisville,, Ky., a corporationof- Delaware Application-March 10, 1948-; Serial rim-14,035

Thisinvention: relates'to sectional dome shaped roofs employed in constructing silos and other small buildings, and: relates: in particular to roofs of the pseudo-spherical type.

A dome or spherical shaped roof possessesgreat rigidity because Of'the curvature of the-roof plates, but entails difliculties in: installation. A true: hemispherical: dome can be made from flat sheets only by an expensive drawing or like operation to curve the sheet in two planes. To eli'minatethe expense of the drawing operation it has been proposed to construct pseudo-spherical domes of cylindrical curved tapered segments. A roof. so constructed is not a true sphere, although; it is generally designated. as spherical. Such a'pseudo-spherical rooiis exemplified by Patents Nos. 2,092,722 to Bangert; 2,151,234 to Rutten et al.; 2,176,712 to Hanson'and 2,187,616 to Cowin.

Pyramidal roofs have been constructed. of triangular sections hooked along' the edges and unitedv by an interlocking C-shap'ed strip slideable.

along the hooked edges,.- as for example, in Patent No. 953,827to Haas. However, this construction has not been employed in dome-shaped roofs, which generally are held assembled by a more complicated structure. Thus, for example, Bangert, supra, employs overlappedzflat roof segments secured together and to internal separate ribs by a multiplicity of bolts passed therethrough and through overlapping strips which seal the joints between segments. His construction requires a relatively long time for assembly because the large size sheets make them awkward to manipulate to secure registration of the bolt holes, and the insertion and tightening of the numerous bolts unduly increases the'time required for assembling the roof. Cowin or Hanson employs roof plates with channeled overlapping edges and internal ribs held together by a multiplicity of bolts along the ribs. The in.- sertion and tightening of: the :bolts in this construction also is time consuming and isdifiicult. Rutten et a1. employsflanged platesand inverted channel members bolted to and overlying -adjacent plates. All the. above pseudo-spherical structures embody a multiplicity. of parts and the structures require considerable time to be assembled.

It is an object of the present invention to provide a dome-shaped; roof structure, of: prefabricated parts, which is of simple construction and which can be assembled at the site in: a-relatively short time.

A. further object is the provisionrof-adome- Claims. (01. ms-32) shapedroof structure composedv of a plurality of segments which-are held assembled by a readily attached clamp strip.

A further object is'the provision-of a dome-' shaped roof structure composed of a plurality of segments? having channelededges, the edges of the segments" being iorm edsubstantiall'yparallel:

to a great circle.

In accordance with the present invention there is provided a. dome-shaped roof composed of. a.

plurality of. segments: each having hooked orf'reverse channel edges on the outer or convexsur face. thereof; so formed that after the sheet is bowed in the curvature of. the dome, theextreme:

. bent over or: free edges. ofthe sheets. lie-substantially parallel to a great circle of-a' sphere. Ad

jacent roof-segments preferably are tiedtogether by a curved double channel locking strip, sub-.

stantially C-shaped'in' cross section. interlocked with the channels on-the' edgesof the segments.

In assembly, the locking strip is applied to one end of the channels of a pair ofadjacent roof segments, and is forced lengthwise overthe adjacent hooked channel "edges of the segments to hold them in assembled relation. .The locking strips then are secured: against accidentalremoval in any suitable-manner. V. The end portions of each segment preferably are cut on curves so that when the segments-areassembled in bowed relation, the lower or wider ends conform substantially to the, equatorial circle of a hemisphere, and the curvature-of the upper or smaller endsare such as to correspond substantially to a small circle parallel to the equatorial circle. The upper ends are secured to aflanged annulus of suitable diameter, and the lower ends are secured toa flanged ring-on. the wallxstructure, preferably by clips which are secured to the roof segments engaging. the: top of the-ring and hook under thefiange.

Itis not necessary that the bottoms of the" channels of the roof segments conform accurately to a. greatrcircle; In some instances; departure from. a. great circle is desirable to allow'io'r 'aberrations inithe silostructure although too great a variation from a great circle makes the roof difcult to assemble. I The bottoms of the channels of. adjacents'eg'ments areheld in positionby engagement'with the 'c shaped locking strip which covers thenioint and makes it weatherproof.

I'n'laying-out the roof segments from flatsheet stock, the number'of. segmentsor' sections being predetermined, the fiat: stock 'is cut to form a segment whose longitudinal or tree edges. are

properly curved." When these edges are properly:

curved and the margins forming them are folded over, such free edges remain curved. However, when the segment is now bowed, the free edges form arcs parallel to a great circle. When the edges are laid out on a convex curve which is substantially the development of a quarter circle on a flat surface, the edges are parallel to the developed great circle and are bent so that the bottoms of the channels conform substantially to a great circle. When laid out on a negative concave curve and the edge portions are bent on a straight line, the channel bottoms of the sheet depart considerably from a great circle, although the bent over edges lie parallel'to .a great circle. If desired, one edge can be-cut convex and the other edge negative or concave so that when the edges are bent over and the segments are assembled, a considerably reduced gap is provided as compared to the structure where the edges are all laid out on a negative or concave curve.

'The invention will be described in greater detail in connection with the accompanying drawing wherein Figures 1-8 disclose one embodi- 4 to form channels 6 and 1, the form of the channels being shown in section in Figure 2. Adjacent segments are held assembled on the roof by a double channeled bowed locking strip 9 which has its edges I I and I2 doubled back to form the opposed channels I3 and I4. In assembled relation the'side edge 4 ofone segment is received within the channel HI on one side of the locking strip, and, on the same side the edge 12 of the locking strip is received in the channel 6 of that segment. The opposed side edge 5 of the adjacent segment is received within the other channel I3.ofthe locking strip, and the edge II of the locking strip is received in the channel I of that segment. The'space I5 between channels 6 and 1 is shown in Figure 2 on an exaggerated scale, and in some instances the exterior surfaces of the channels 6 and I will be in contact ment of my invention and Figures 9-14 another embodiment, and wherein Figure 1 is a side elevation with parts broken away showing a roof constructed according to the 1 Figure 6 is a side elevation of a curved roof 7 segment embodying my invention and ready for assembly,

Figures 7 and 8 illustrate one method of developing the roof segment illustrated in Figure 6, Figure 9 shows a modified form of roof se ment before it is bowed,

Fi ure 10 is a fragmentary plan view of a roof constructed of segments illustrated in Figure 9,

Figure 11 is a side elevation of Figure 10 with parts broken away,

Figure 12 illustrates the development of the segment shown in Figure 9,

Figure 13 is a section along line |3I3 of Figure 10, omitting the ring I; and

Figure 14 is a section taken along line I I-I4 of Figure 10.

Referring to the drawing, Figures 1 to 5, the wall structureof the building carries a ring -'I which preferably is L-shaped in cross-section, to which the bottom. of the roof structure is fastened, as will hereinafter appear. The roof comprises a plurality of segments 2, 2a, etc. 211., which may be alike, and each of which is curved substantially upon a radius R, so .that

side edges 4 and 5 doubled back or reversely bent throughout their length, thus substantially eliminating the space I5. At the top, the roof segments support a ventilator ring member I6 having a conical flange I1 (Fig. 4) to which the roof segments are secured by bolts I8 passing through the locking strip and through notches I9 and 2I of adjacent roof segments near the top edge 22. Adjacent the bottom edge 24, (Fig. 5) bolts 25 pass through the locking strip and notches 26, 21 (Fig. 6) of adjacentroof segments to secure an angular hook 28 thereto, the end 29 of the hook engaging around the ring I,

secured to the silo wall, by which the roof is 2 scribed: Referring to Figure 3 the bottom ring I is "suitably secured to the silo wall and the top ring I6 is suitably braced in position while two adjacent segments 2 and 2a are positioned between the rings and may be secured thereto by bolts 30 passing through ring I6. A bowed locking strip 9 now is applied at the upper edges 22 of the segments in interlocking relation, with edges 4 and 5 of the segments received in channels I4 and I3 respectively of the strip, and edges II and I2 of the strip received in channels I and 6 respectivelyof the segments. The strip now is slid downward in this relation until the ends of the strip coincide with the lower and upper ends of the roof segments. A bolt 18 then is passed through a preformed hole in the locking strip, through the mating notches I9, ZI of adjacent segments, and through a preformed hole in ring I6, and is held in position by a suitable nut. At the bottom, a bolt 25 is passed through a preformed hole in the locking strip and through mating notches 25, 21 of adjacent segments. The end 29 of hook 28 is engaged under ring I and the bolt 25 is received in a suitable hole in the other end of the hook, the bolt being retained by a suitable nut.

Having thus secured two segments together and to the rings I and I6, another pair of segments are positioned substantially diametrically opposite and the assembly operation repeated with the second pair of segments. Then, a pair of segments are similarly assembled in each roof quadrant, and the spaces between assembled segments progressively filled in by segments which are locked to the adjacent segments. By proceeding in this manner instead of assembling the segments progressively around the dome, the spacing l5 between the segments is more or less evenly distributed about the dome, so that no difficulty is encountered in'positioning the last segment in place. The bolts then are all tightened. Although in Figure 2 the segment edges diameter of the roof as viewed in plan.

economize on space in the drawing, only'a quadsteam 4 and dare shown spaced: from the bottomsfof channels I4 and I 3, and the edges II and I! are shown spaced from channels "I and 6, it is to be understood that, depending on the width of the reversed edge portions, some or all of the segment edges will engage the bottoms of the channels of the locking strip. Also, the exterior'edges of channels 6 and lot adjacentsegments will contact at one or more points so" that at such contacting points space I is eliminated. p The bolts 25 and hooks 28 anchor the roo'f' to the silo wall, the hooks allowing for aberrations of the wall from a true circle. At the top, the bolts l8 tie the roof to the ring l6 which receives a ventilator fitting. These bolts also prevent the locking strips 9 from sliding out ofposition; It will be understood that if desired, other means may beprovided for this purpose.

The roof illustrated and described can be shipped either fiat or bowed, and can be assembled quickly and easily, and there are relatively few bolts to be inserted. The bolts employed pass between adjacent segments, so that this construction avoids the difliculties encountered in prior dome structures which require alignment of bolt holed in overlapping springy loose metal members. Furthermore, by eliminating bolts intermediate the ends, the inconvenience'and difficulties attending the insertion of the bolts'in springy. portions of the roof is avoided. ROOfs' of this type may range in size up to about twenty feet in diameter, and becauseof the steep pitch of the dome a man cannot securely cling to the dome at the middle to apply bolts through the roof. In addition, the weight of the roof, compared with prior dome structures is decreased, and lighter gauge metal can be .used for the segments.

- The segments can be laid out by several development methods, and one such method now will be described. Referring to Figure 7, a circle is laid out from the center 0, the equatorial diameter of the circle along line A0 being the To rant OAB of the circle is shown; and corresponding points on the arc of the adjacent quadrant are represented by theprimed letters. Thus, AA represents the diameter equal to twice the radius 0A. The point C represents the end of the dome at the-annulus l6. The are AC is now divided into any desired number of equal spaces AD, DE, etc., seventeen such spaces beingshown. The points D, 'E, etc. now are projected horizontally parallel to diameter line A0, to form chords DD, EE', etc., CC,.Which are diameters of small circles of a sphere. The circumference of the circle of diameter AA is calculated, and

distance BA. 'The next circle D is. drawn on a,

radius equal to the arcuate distance BD, etc. until the last circle C, drawn on the radius of arcuate distance BC, is scribed. Assuming, for illustration, that the roof will contain fourteen segments, the circumference of the great circle of diameter AA is divided by 211, or twenty-eight, and this value, designated'as XK is laid out on the arc of circle A (Figure 8) on each side of the center line. The circumference'bf asmall circle of diameter DD n'owis calculated and divided by 272, and this value XL is laid out on the arc of circle D on each side of the center line. Similarly the circumference of a' small circle of diameterEE' '"divided by 2n is laid out on each side of the center on are of circle E, etc., and finally the circumference of the small circle of diameter CC is laid out on circle C to provide the value XY. Now, a curve is drawn joining the lines YK. Now when the sheet is cut the edges Y'K' represent free edges 4 and 5-of Figure 6. These edges then are reversely bent along both fold lines YK so that the arc YY' represents the top edge 22, and are KK represents the'bottom' edge 24. The channels 6 and 1 now are formed at the edges, and then the sheet is bowed upon a radius R (Figure 1) to conform to a cylindrical surface. In elevation the bowed segment will appear substantially as shown in Figure 6, with the top and bottom edges 22, 24 appearing substantially as straight lines. The bottom edge 24 conforms substantially to an equatorial circle. and edge 22 conforms to a small circle parallel to the equatorial circle. The reversed edges 4 and lie on the convex side of the segment, and as the channel bottoms 6 and 1 lie substantially on great circles of the sphere, the edges 4- and 5 are parallel thereto. Thus, eachsegment constitutes avcurved surface tangent to a sphere along the of the segment makes a median reenforcement' desirable, and to provide for the formation of this rib an additional constant amount is added to the values K'K', LL, etc.-' Now, when the median rib is formed thisadded material is taken up in the rib, and the edges then are turned back and the, unit ,is bowed to form a roof segment. It .is apparent that as each segment includes allowance for the edge channels, and mayinclude allowance for the rib 36, that these allowances must be included in determining the width of the sheet required for each segment. This modification is bowed before shipment to the erecting site. If desired, more than one rib 36 may be provided, in which case the ribs are symmetrically arranged about the middle of each segment.

In the modification illustrated in Figures 9 to 11 wherein like parts are designated by like reference numerals, the modified roof segments 40', Mia, etc. 4011 are secured together by strips 9 as previously described in connection with the development of thesegments. The segment is laid out on a flat sheet 4| as shown in Figures 9 and l2, with the edges 22 and 24 developed by the curves YY and KK as described in connection with Figure 8. To develop the side edges 42 and 43, a flat unit cut out on the lines of mates;

ure .8 isipnsei-qnashe tw etal 4 ai tt;

its}; mar n s makes an anglewith the center-} in "O -smash d... s an e -3 v ed bat e-n mb s he tsi ns men n i h and provide a space 5 therebetween which tapers gradually froma maximum-at. about the middle as shown;in- Figure -l ig toward both ends of the segmentpwhere the: space is substantially closed,

asgshowndn Figure ,13. Because the end chan-.

nels 44-, 45 thus formed in the segments are deeper at .-the ends than at the-middle, the double chan nel stripg is made wider. Also, because the relative large space li-makes assembly of the seg ments more difficult it is preferred to brace the ventilator ring l6 by means of suitable stay bars 41; (Figure1l) welded thereto and to the ring I. Three such stay bars preferably are employed.

This modification is assembled the'same as that illustrated in Figures. 1 to 5; After securing two roof segnients inplace a curved clamping strip 9; is; slid overthe adjaccnt.;channel members of adjacent-segments, the root being secured to the top and bottom-rings; as previously described.

The roof;- constructed according to the present invention -is of lightweightbutrig id, and is easily and quicklmassembled; If desired one edge 'of each segment. may beiformedparallel to a developed great circle,and the other edge parallel to a negative development of a great circle. Each edge thus willbe parallel to a great circle after it. is reversely folded; and a .bowedlocking strip,- intermediatein width between that employed in the modification of Figures .1 'to 6, and that in Figures 19 to 11, is .employedto hold the segments assembled. In such modification the space l5 will be somewhat narrower at its mid point than inthe modification-.shownin Figures '9 to 11. It will be.understoodthatprimarily the edges of the-roof segment sheets, are substantially parallel and that it is not necessary that the bottoms of the segment channels be incontact or even parallel, although contact at; two or more points is preferred.- Variousmodifications maybe made inthezinvention without departing from the spirit orscope thereof 7 It gwill be' appreciated thatthe embodiments shown Figuresl- B andFigures 9-14, relate to a semi-sphericalroof composedxof a horizontal succession or-vertically. extending and tapering sections,- Each section 'curves upwardly from a base, circle extending--- concentrically around the vertical, axis of the sphere. to. a smaller similarly extending icirclei. Each curved section alsohas it s side margins lbent overits convex face to form opposedchannels which openLtoward each other;

. Each oithese channels has a bight'orfold edge,

which, when the sections are. in assembled relationship, oppose the adjacent. fold edge. of an 1 adjacent section. at f a joint. line which. extends. between them aloh la great circle of the-sphere.

Each channel also has a straight circular'free edgewhich extendsin parallel relationship topthe,

d a enti e t irel e b et ine- BY s r ht edges 42-, 43 ,become'the positive develop-- 8? r ula which ex nds along th planaof ai'circle without departing; substantiall H from such plane. This circle-need; notbe a true a circle but, in the preferred embodiment is as true as can readily be attained instructures ofzthis character.

It;-v;willn0wbe appreciated that, when this straight. circular. free; edge, which is designated by, the. numeral; 4 in the embodiment of Figures 1-8 and by the numeral 14- in the embodiment of Figures 9-14 is developed upon a plane surface, it willnecessarily form-. an edgev outline of predetermined concave curvature. The reverse is true. Hence, if the flat blank,;for a given finished curved section, is provided with side marginal channels facing-each; other. and if the free edge of each channelis trimmed; or otherwise arranged to present said predetermined concave curvature (which coincides with the concave outline formed by the plane;surfacedevelopment.of' the circular free edgegof: theicorrespondmg channel; on the finishedsection), then, whensuch fiat channeled blankiiscylindrically; bent longitudinally to the great; circle. curvature. of thesphere, the concaveifreeedge ofeach channel will straighten out tojform the aforesaidgcircular edge. This is preciselywhatisdoneiin the process of making each of theembodiments, of Figures 1-8 and 9-14.

Thus. in the first embodiment, the side edges are trimmed to: a. convex curvature. Each side margin is;..then..folded; over. a,similarly. curved fold line to form: the channels; The curvature of each edge and of the adjacentfold'lineis not only the same but is predetermined to cause the free edge automatically to 'have thezdesired concavity when it:is:folded over. This may beclear upon realizing that'rthe fold line has av convex side and a concave side and that its concave curvature is parallel. to the desired concave outline fornied by said plane surfacedevelopment.

In Figures 9-14, the'flat blank is provided with side edges which are formed with the same concave curvature that is formedby said plane surface development. When this margin is bent over-a straight fold line, it retains the same concavecurvature which isnow positioned to coincide with the concave outline formed by said plane surface development We claim as our invention:

1. A pseudo-spherical dome roof comprising a plurality of roof segments each bowed to conform substantially to the surface of a cylinder and having reversed side margins forming side channels which longitudinally extend in the direction of -the bow and transversely overlie the convex side of the segment and which have bight and free'edges, the free edgeof each channel being substantially parallelto a'greatcircle of a sphere; and adouble channel curved strip of substantially uniform width receivingsaid reversed margins-of adjacent segments for holding said segments in assembled relation.

2. A dome roof as-specified in claim 1 wherein thelbight of at least one channel of each segment lying the convex side of the segment, each channel having a bight and a free edge and each free edge being substantially parallel to a great circle of a sphere.

6. A segment for a dome-shaped roof as specifled in claim 5 wherein the bights of said channels conform substantially to great circles.

7. A segment as specified in claim 5 wherein the bight of at least one of said channels developed on a plane surface presents a substantially straight line.

8. A unit for a dome-shaped roof comprising a bowed segment having a bottom edge and reversed side margins forming side channels which overlie the convex side of the segment and which have bight and free edges, the latter being substantially parallel to a great circle of a sphere; said segment having an embossed rib formed substantially along the median line thereof.

9. An improved section for semi-spherical roofs, of the type composed of a horizontal succession of sections wherein each section curves and tapers upwardly, from a base circle extending concentrically around the vertical axis of the sphere to a smaller similarly extending circle, with each of its upwardly curved side margins opposing the similarly curved side margin of an adjacent section at a joint line which also curves upwardly along a great circle of the sphere, comprising:

a curved section of the foregoing character having its side margins bent over its convex face to form opposed channels which open toward each other, each channel having an upwardly curved bight or fold edge. which when the sections are in assembled relationship opposes the adjacent similarly curved fold edge of an adjacent section along the great circle joint line extending between them, and a straight circular free edge which is substantially parallel to said great circle joint line.

10. An improved semi-spherical roof comprising: a horizontal succession of sections, each section curving and tapering upwardly, from a base circle extending concentrically around the vertical axis of the sphere to a smaller similarly extending circle, with each of its side margins opposing the adjacent side margin of an adjacent section at a joint line which extends along a great circle of the sphere, each curved section having its side margins bent over its convex face to form opposed channels which open toward each other, each channel having a bight or fold edge which, when the sections are in assembled relationship, opposes the adjacent fold edge of an adjacent section along the great circle joint line extending between them and a straight cir- 7 cular freeedge which is substantially parallel to said great circle joint line; and means for securing said sections together in assembled relationship, said means including a securing strip of substantially uniform width, and of C-shape in cross section to provide opposed grooves opening toward each other, said strip being arranged over the great circle joint line between adjacent sections with one of its grooves receiving the adjacent straight circular free edge of the channel on one section and with its other groove receiving the adjacent straight circular free edge of the channel on the adjacent section.

ROBERT S'IEMMONS.

WALTER L. EDEL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

